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[Display omitted] • We develop a PEDOT-MeOH:PSS/PDA interface by a two-step electropolymerization method. • The prepared interface shows strong adhesion with 93% area retention after sonication for 20 min. • We further demonstrate the PEDOT-MeOH:PSS/PDA interface integrated on an ultrasmall Pt-Ir wire microelectrode with a diameter of only 10 μm. • The modified implantable neural microelectrodes display two orders of magnitude lower impedance than commercial products, and also superior long-term stability after 10,000,000 biphasic input pulse cycles. Conducting polymers are emerging as promising neural interfaces towards diverse applications such as deep brain stimulation due to their superior biocompatibility, electrical, and mechanical properties. However, existing conducting polymer-based neural interfaces still suffer from several challenges and limitations such as complex preparation procedures, weak interfacial adhesion, poor long-term fidelity and stability, and expensive microfabrication, significantly hindering their broad practical applications and marketization. Herein, we develop an adhesive and long-term stable conducting polymer neural interface by a simple two-step electropolymerization methodology, namely, the pre-polymerization of polydopamine (PDA) as an adhesive thin layer followed by electropolymerization of hydroxymethylated 3,4-ethylenedioxythiophene (EDOT-MeOH) with polystyrene sulfonate (PSS) to form stable interpenetrating PEDOT-MeOH:PSS/PDA networks. As-prepared PEDOT-MeOH:PSS/PDA interface exhibits remarkably improved interfacial adhesion against metallic electrodes, showing 93% area retention against vigorous sonication for 20 min, which is one of the best tenacious conducting polymer interfaces so far. Enabled by the simple methodology, we can facilely fabricate the PEDOT-MeOH:PSS/PDA interface onto ultrasmall Pt-Ir wire microelectrodes (diameter: 10 μm). The modified microelectrodes display two orders of magnitude lower impedance than commercial products, and also superior long-term stability to previous reports with high charge injection capacity retention up to 99.5% upon 10,000,000 biphasic input pulse cycles. With these findings, such a simple methodology, together with the fabricated high-performance and stable neural interface, can potentially provide a powerful tool for both advanced neuroscience researches and cutting-edge clinical applications like brain-controlled intelligence. [ABSTRACT FROM AUTHOR]

Summary: Poly(2,7‐bis(carbazol‐9‐yl)‐9,9‐dimethylfluorene) (PBCMF) polymer with porous structure was fabricated, and its electropolymerization was studied comparatively in dichloromethane (CH2Cl2) systems in the presence of different contents of boron trifluoride diethyl etherate (BFEE). When adding BFEE in CH2Cl2 solution, the oxidation potential of BCMF could be decreased obviously. When the content of BFEE increased to 40%, BCMF was oxidized at 0.47 V, while it was oxidized at 1.07 V in pure CH2Cl2 solution. A series of experiments showed that the polymer PBCMF films could be easily obtained in CH2Cl2‐BFEE systems, and films obtained from the 40 vol% BFEE system showed best electrochemical behavior and best fluorescence property. Fourier transform infrared spectra and UV‐Vis proved the longer conjugated chains of polymers. And scanning electron microscopy images of polymer films showed that all these polymer films made from BFEE systems had a good porous structure. [ABSTRACT FROM AUTHOR]

Electrochromic devices based on high-performance polymer materials with exceptional optical contrast, superior cycling stability, and large coloration efficiency are critical for the advancement of electrochromics, and have the potential to innovate a broad range of applications, including flexible displays and wearable electronics. Here, we design and synthesize three precursors of fluorobenzene-3-methylthiophene D-A-D type polymers through one-step Stille coupling, and then prepare the corresponding polymer films with good electrochemical and electrochromic properties via low-potential electropolymerization at 0.52 V vs Ag/AgCl. Interestingly, such polymers exhibit overall high electrochromic performances during the electrochemical reaction with inversible color changes between yellow and dark blue, including high optical contrast (83% at 1050 nm), fast response time (1.4 s / 0.8 s), and long-term stability (< 2% reduction after 250 cycles). As-fabricated electrochromic devices display excellent cycling stability (< 3% optical contrast degradation after 1,000 cycles) at a low drive voltage (0.8 V). Due to these excellent electrochromic properties, d -A-D type polymers based on fluorobenzene-3-methylthiophene can be further developed for practical applications such as near-infrared camouflage and E-displays. [Display omitted] [ABSTRACT FROM AUTHOR]

High polymerization degree is critical for polypyrene applying in fluorescent sensing field, which closely related to high sensitivity. However, polypyrene films reported are either insoluble and unprocessable or soluble with few repeat units. In this work, we synthesized a poly(1-pyrenebutyric acid) (PPBA) via electrochemical polymerization in boron fluoride ethyl ether system and the degree of polymerization was up to 43, which showed good fluorescence. The polymer showed high selectivity toward to Cr 2 O 7 2− among sixteen anions and twenty cations in ethyl alcohol system, and the limit of detection was as low as 1.58 fM. Transmission electron microscope results showed that the quenching mechanism of the PPBA was Cr 2 O 7 2−-induced inter- and intra-polymer aggregation of polymer chains in solution. Finally, PPBA was successfully applied in milk detection, implying that PPBA can realize the ultra-trace detection of Cr 2 O 7 2− in practical application. High degree of polymerization of poly(1-pyrenebutyric acid) fluorescence sensor that can specifically recognize Cr 2 O 7 2−. [Display omitted] • The fluorescence sensor PPBA with high polymerization degree was obtained by electropolymerization. • PPBA was highly sensitive to Cr 2 O 7 2− and the limit of detection was as low as 1.58 fM. • PPBA had a high anti-interference ability when sensing Cr 2 O 7 2−, avoiding the interference of common anions and cations. • PPBA was successfully used to detect Cr 2 O 7 2− in milk. [ABSTRACT FROM AUTHOR]